There are plenty of words you could use to describe the first-gen Jaguar XJ-S, a 12-cylinder British-built muscle car launched right in the middle of the malaise era. The nice way to describe it may be “misguided.” In defense of the XJ-S, it’s a good-looking car, and 7.6 seconds was a really good 0-60 time for a car in the oil crisis years. But, by and large, the XJ-S was the product of a whole series of questionable decisions.

At present, Jaguar has been talking about going fully electric with models like the F-Pace, and it’s unclear what the brand’s prospects are going into the next few years. Say what you will of the automaker, but Jaguar has always been a company that’s swung for the fences, and that’s something worth acknowledging whether or not every idea is a winner. The XJ-S was nothing if not bold.

A Look At The 1975 Jaguar XJ-S

When you learn that Jaguar built a 12-pot muscle car right in the middle of the oil crisis, your first question is naturally going to be “what the hell were they thinking?” Well, to be fair, the XJ-S hit the market in the mid-1970s, but Jaguar had been developing the car for nearly a decade. The car makes a lot more sense as a late-’60s concept, something from the golden age of the muscle car, and that’s when the first designs for the car, then code named Project XJ27, were drawn up by Malcolm Sayer.

Malcolm Sayer had a strong hand in giving Jaguar its signature look, having designed iconic models like the C-Type and the XJ13 prototype. Unfortunately, Sayer suffered a fatal heart attack at the age of 53 in 1970, before he could put the finishing touches on the XJ-S. You might say that the completion of the car’s design, under the oversight of Doug Thorpe, was a way of keeping Sayer’s legacy alive, even as it would soon become increasingly clear that the market was unlikely to take to a 5.3-liter V12 grand tourer by the mid-1970s.

Jaguar Struggled To Sell The XJ-S

Jaguar produced 14,800 units between 1975 and 1981, eventually halting production halfway through the final year in order to focus on unloading existing stock. It’s not hard to guess that a V12 would be a slow-seller in the oil crisis era, but the car’s piddly fuel economy, averaging as little as 11 mpg in the city, wasn’t its only problem.

Those big, obtrusive buttresses behind the windows lend the car its signature look, but they also created a visibility concern, which wound up with German XJ-S buyers having to obtain road approval on each individual model, as the country’s highway authorities wouldn’t certify the nameplate itself. No doubt, this took a significant bite out of European sales.

Vintage Jaguar enthusiasts have noted that the XJ-S is incredibly rust-prone, and loaded with plastic and rubber parts that have become brittle with age, some of which may be impossible to replace. It should also be noted that this is one of those cars that will have you going over every joint and chain with an oil can to ensure proper lubrication. So the car had more than its share of problems on release, and it hasn’t aged well, either.

For some reason, Leyland Cars decided to give the XJ-S a second chance, launching the XJ-S HE in 1981. HE stood for High-Efficiency, referring to the redesigned V12 engine that would carry the XJ-S to 295 hp in the 1980s. The car would also be offered with a 3.6-liter straight-six engine. Jaguar wound up producing 73,207 of these throughout the 1980s, and then 27,406 of the facelifted version from 1991 to 1996 under Ford ownership. So the XJ-S would go on to become an attractive muscle car across two more decades, despite this awkward first impression.

The Right Engine At The Wrong Time

The frustrating thing about the XJ-S is that there’s a lot to like about the V12 under its hood. 1975 was just the worst possible time to try and sell something like this to the general public.

The V12 had a compression ratio of 7.8:1 in the US model, or 9:1 in the European model. It was part of the larger Jaguar V12 engine family, built on the XJ13 prototype engine, with aluminum cylinder blocks and heads, and cast-iron cylinder liners. The engine made its debut in the Jaguar E-Type, and, in the early 1970s, could also be found in the 1972 XJ12, and the Daimler Double-Six.

Jaguar’s V12 family wound up having a long life under the hoods of various Jaguars, covering about a quarter-century from 1991 to 1997, with 161,583 units having been produced across the 5.3, 6.0, and 7.0 iterations.

The 7.0-liter delivered 496 hp at its base, but, at its most powerful, the V12 could be pushed upwards of 600 horses. An aftermarket Jaguar tuner, Lister Cars, sold a modified XJ-S in 1991 with a twin-supercharged 7.0-liter V12 cranked up to 604 hp, and we’ve seen the engine tuned up to well beyond that in the TWR Super Cat.

What Will A Jaguar XJ-S Cost You In 2025?

All versions of the Jaguar XJ-S are pretty rare. They do appear for sale a little more frequently over the pond, though, and we found a 1970s XJ-S in right-hand-drive model on Bonhams, which sold recently for £14,900, or about $20,000 in USD. Other sold examples in good condition seem to command similar figures.

The XJ-S models we turned up were mostly from the 1990s. To go over our Bring a Trailer findings right quick…

• A 45,000-mile 1995 XJ-S Convertible selling for $10,000 in early 2024.
• A 91,000-mile 1994 XJ-S Convertible selling for $7,181 in mid-2024.
• A 76,000-mile 1985 XJ-S Coupe selling for $8,107 in mid-2021.
• A 15,000-mile 1994 XJ-S Convertible selling for $16,250 in August 2025.
• A 17,000-mile 1991 XJ-S Convertible selling for $15,000 in mid-2025.

So there’s good news, bad news, and good news. The good news is that these cars tend to go for pretty cheap. The bad news is that it’s incredibly hard to find a 1970s model in any condition. But the good news is that you don’t really want a 1970s XJ-S. The High-Efficiency models produced in the 1980s have been reported to get up to 25 miles to the gallon on the highway, and they delivered 295 hp, a 10-point boost over the earlier model, and the 1990s models averaged around 13/18 mpg, city/highway.

If you want to hold out for a 1970s model XJ-S, the car is more interesting as an historical oddity these days than it is a viable daily-driver or weekend warrior. It’s inefficient and high-maintenance, and you’ll be lucky to find one in any condition in 2025.

Sources: Jaguar, Bring a Trailer, Bonhams Cars Online.